xref: /openbmc/linux/arch/sparc/kernel/vio.c (revision 2fa49589)
1 // SPDX-License-Identifier: GPL-2.0
2 /* vio.c: Virtual I/O channel devices probing infrastructure.
3  *
4  *    Copyright (c) 2003-2005 IBM Corp.
5  *     Dave Engebretsen engebret@us.ibm.com
6  *     Santiago Leon santil@us.ibm.com
7  *     Hollis Blanchard <hollisb@us.ibm.com>
8  *     Stephen Rothwell
9  *
10  * Adapted to sparc64 by David S. Miller davem@davemloft.net
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/irq.h>
16 #include <linux/export.h>
17 #include <linux/init.h>
18 
19 #include <asm/mdesc.h>
20 #include <asm/vio.h>
21 
22 static const struct vio_device_id *vio_match_device(
23 	const struct vio_device_id *matches,
24 	const struct vio_dev *dev)
25 {
26 	const char *type, *compat;
27 	int len;
28 
29 	type = dev->type;
30 	compat = dev->compat;
31 	len = dev->compat_len;
32 
33 	while (matches->type[0] || matches->compat[0]) {
34 		int match = 1;
35 		if (matches->type[0])
36 			match &= !strcmp(matches->type, type);
37 
38 		if (matches->compat[0]) {
39 			match &= len &&
40 				of_find_in_proplist(compat, matches->compat, len);
41 		}
42 		if (match)
43 			return matches;
44 		matches++;
45 	}
46 	return NULL;
47 }
48 
49 static int vio_hotplug(struct device *dev, struct kobj_uevent_env *env)
50 {
51 	const struct vio_dev *vio_dev = to_vio_dev(dev);
52 
53 	add_uevent_var(env, "MODALIAS=vio:T%sS%s", vio_dev->type, vio_dev->compat);
54 	return 0;
55 }
56 
57 static int vio_bus_match(struct device *dev, struct device_driver *drv)
58 {
59 	struct vio_dev *vio_dev = to_vio_dev(dev);
60 	struct vio_driver *vio_drv = to_vio_driver(drv);
61 	const struct vio_device_id *matches = vio_drv->id_table;
62 
63 	if (!matches)
64 		return 0;
65 
66 	return vio_match_device(matches, vio_dev) != NULL;
67 }
68 
69 static int vio_device_probe(struct device *dev)
70 {
71 	struct vio_dev *vdev = to_vio_dev(dev);
72 	struct vio_driver *drv = to_vio_driver(dev->driver);
73 	const struct vio_device_id *id;
74 
75 	if (!drv->probe)
76 		return -ENODEV;
77 
78 	id = vio_match_device(drv->id_table, vdev);
79 	if (!id)
80 		return -ENODEV;
81 
82 	/* alloc irqs (unless the driver specified not to) */
83 	if (!drv->no_irq) {
84 		if (vdev->tx_irq == 0 && vdev->tx_ino != ~0UL)
85 			vdev->tx_irq = sun4v_build_virq(vdev->cdev_handle,
86 							vdev->tx_ino);
87 
88 		if (vdev->rx_irq == 0 && vdev->rx_ino != ~0UL)
89 			vdev->rx_irq = sun4v_build_virq(vdev->cdev_handle,
90 							vdev->rx_ino);
91 	}
92 
93 	return drv->probe(vdev, id);
94 }
95 
96 static int vio_device_remove(struct device *dev)
97 {
98 	struct vio_dev *vdev = to_vio_dev(dev);
99 	struct vio_driver *drv = to_vio_driver(dev->driver);
100 
101 	if (drv->remove) {
102 		/*
103 		 * Ideally, we would remove/deallocate tx/rx virqs
104 		 * here - however, there are currently no support
105 		 * routines to do so at the moment. TBD
106 		 */
107 
108 		return drv->remove(vdev);
109 	}
110 
111 	return 1;
112 }
113 
114 static ssize_t devspec_show(struct device *dev,
115 		struct device_attribute *attr, char *buf)
116 {
117 	struct vio_dev *vdev = to_vio_dev(dev);
118 	const char *str = "none";
119 
120 	if (!strcmp(vdev->type, "vnet-port"))
121 		str = "vnet";
122 	else if (!strcmp(vdev->type, "vdc-port"))
123 		str = "vdisk";
124 
125 	return sprintf(buf, "%s\n", str);
126 }
127 static DEVICE_ATTR_RO(devspec);
128 
129 static ssize_t type_show(struct device *dev,
130 		struct device_attribute *attr, char *buf)
131 {
132 	struct vio_dev *vdev = to_vio_dev(dev);
133 	return sprintf(buf, "%s\n", vdev->type);
134 }
135 static DEVICE_ATTR_RO(type);
136 
137 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
138 			     char *buf)
139 {
140 	const struct vio_dev *vdev = to_vio_dev(dev);
141 
142 	return sprintf(buf, "vio:T%sS%s\n", vdev->type, vdev->compat);
143 }
144 static DEVICE_ATTR_RO(modalias);
145 
146 static struct attribute *vio_dev_attrs[] = {
147 	&dev_attr_devspec.attr,
148 	&dev_attr_type.attr,
149 	&dev_attr_modalias.attr,
150 	NULL,
151  };
152 ATTRIBUTE_GROUPS(vio_dev);
153 
154 static struct bus_type vio_bus_type = {
155 	.name		= "vio",
156 	.dev_groups	= vio_dev_groups,
157 	.uevent         = vio_hotplug,
158 	.match		= vio_bus_match,
159 	.probe		= vio_device_probe,
160 	.remove		= vio_device_remove,
161 };
162 
163 int __vio_register_driver(struct vio_driver *viodrv, struct module *owner,
164 			const char *mod_name)
165 {
166 	viodrv->driver.bus = &vio_bus_type;
167 	viodrv->driver.name = viodrv->name;
168 	viodrv->driver.owner = owner;
169 	viodrv->driver.mod_name = mod_name;
170 
171 	return driver_register(&viodrv->driver);
172 }
173 EXPORT_SYMBOL(__vio_register_driver);
174 
175 void vio_unregister_driver(struct vio_driver *viodrv)
176 {
177 	driver_unregister(&viodrv->driver);
178 }
179 EXPORT_SYMBOL(vio_unregister_driver);
180 
181 static void vio_dev_release(struct device *dev)
182 {
183 	kfree(to_vio_dev(dev));
184 }
185 
186 static ssize_t
187 show_pciobppath_attr(struct device *dev, struct device_attribute *attr,
188 		     char *buf)
189 {
190 	struct vio_dev *vdev;
191 	struct device_node *dp;
192 
193 	vdev = to_vio_dev(dev);
194 	dp = vdev->dp;
195 
196 	return snprintf (buf, PAGE_SIZE, "%pOF\n", dp);
197 }
198 
199 static DEVICE_ATTR(obppath, S_IRUSR | S_IRGRP | S_IROTH,
200 		   show_pciobppath_attr, NULL);
201 
202 static struct device_node *cdev_node;
203 
204 static struct vio_dev *root_vdev;
205 static u64 cdev_cfg_handle;
206 
207 static const u64 *vio_cfg_handle(struct mdesc_handle *hp, u64 node)
208 {
209 	const u64 *cfg_handle = NULL;
210 	u64 a;
211 
212 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
213 		u64 target;
214 
215 		target = mdesc_arc_target(hp, a);
216 		cfg_handle = mdesc_get_property(hp, target,
217 						"cfg-handle", NULL);
218 		if (cfg_handle)
219 			break;
220 	}
221 
222 	return cfg_handle;
223 }
224 
225 /**
226  * vio_vdev_node() - Find VDEV node in MD
227  * @hp:  Handle to the MD
228  * @vdev:  Pointer to VDEV
229  *
230  * Find the node in the current MD which matches the given vio_dev. This
231  * must be done dynamically since the node value can change if the MD
232  * is updated.
233  *
234  * NOTE: the MD must be locked, using mdesc_grab(), when calling this routine
235  *
236  * Return: The VDEV node in MDESC
237  */
238 u64 vio_vdev_node(struct mdesc_handle *hp, struct vio_dev *vdev)
239 {
240 	u64 node;
241 
242 	if (vdev == NULL)
243 		return MDESC_NODE_NULL;
244 
245 	node = mdesc_get_node(hp, (const char *)vdev->node_name,
246 			      &vdev->md_node_info);
247 
248 	return node;
249 }
250 EXPORT_SYMBOL(vio_vdev_node);
251 
252 static void vio_fill_channel_info(struct mdesc_handle *hp, u64 mp,
253 				  struct vio_dev *vdev)
254 {
255 	u64 a;
256 
257 	vdev->tx_ino = ~0UL;
258 	vdev->rx_ino = ~0UL;
259 	vdev->channel_id = ~0UL;
260 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
261 		const u64 *chan_id;
262 		const u64 *irq;
263 		u64 target;
264 
265 		target = mdesc_arc_target(hp, a);
266 
267 		irq = mdesc_get_property(hp, target, "tx-ino", NULL);
268 		if (irq)
269 			vdev->tx_ino = *irq;
270 
271 		irq = mdesc_get_property(hp, target, "rx-ino", NULL);
272 		if (irq)
273 			vdev->rx_ino = *irq;
274 
275 		chan_id = mdesc_get_property(hp, target, "id", NULL);
276 		if (chan_id)
277 			vdev->channel_id = *chan_id;
278 	}
279 
280 	vdev->cdev_handle = cdev_cfg_handle;
281 }
282 
283 int vio_set_intr(unsigned long dev_ino, int state)
284 {
285 	int err;
286 
287 	err = sun4v_vintr_set_valid(cdev_cfg_handle, dev_ino, state);
288 	return err;
289 }
290 EXPORT_SYMBOL(vio_set_intr);
291 
292 static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
293 				      const char *node_name,
294 				      struct device *parent)
295 {
296 	const char *type, *compat;
297 	struct device_node *dp;
298 	struct vio_dev *vdev;
299 	int err, tlen, clen;
300 	const u64 *id, *cfg_handle;
301 
302 	type = mdesc_get_property(hp, mp, "device-type", &tlen);
303 	if (!type) {
304 		type = mdesc_get_property(hp, mp, "name", &tlen);
305 		if (!type) {
306 			type = mdesc_node_name(hp, mp);
307 			tlen = strlen(type) + 1;
308 		}
309 	}
310 	if (tlen > VIO_MAX_TYPE_LEN || strlen(type) >= VIO_MAX_TYPE_LEN) {
311 		printk(KERN_ERR "VIO: Type string [%s] is too long.\n",
312 		       type);
313 		return NULL;
314 	}
315 
316 	id = mdesc_get_property(hp, mp, "id", NULL);
317 
318 	cfg_handle = vio_cfg_handle(hp, mp);
319 
320 	compat = mdesc_get_property(hp, mp, "device-type", &clen);
321 	if (!compat) {
322 		clen = 0;
323 	} else if (clen > VIO_MAX_COMPAT_LEN) {
324 		printk(KERN_ERR "VIO: Compat len %d for [%s] is too long.\n",
325 		       clen, type);
326 		return NULL;
327 	}
328 
329 	vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
330 	if (!vdev) {
331 		printk(KERN_ERR "VIO: Could not allocate vio_dev\n");
332 		return NULL;
333 	}
334 
335 	vdev->mp = mp;
336 	memcpy(vdev->type, type, tlen);
337 	if (compat)
338 		memcpy(vdev->compat, compat, clen);
339 	else
340 		memset(vdev->compat, 0, sizeof(vdev->compat));
341 	vdev->compat_len = clen;
342 
343 	vdev->port_id = ~0UL;
344 	vdev->tx_irq = 0;
345 	vdev->rx_irq = 0;
346 
347 	vio_fill_channel_info(hp, mp, vdev);
348 
349 	if (!id) {
350 		dev_set_name(&vdev->dev, "%s", type);
351 		vdev->dev_no = ~(u64)0;
352 	} else if (!cfg_handle) {
353 		dev_set_name(&vdev->dev, "%s-%llu", type, *id);
354 		vdev->dev_no = *id;
355 	} else {
356 		dev_set_name(&vdev->dev, "%s-%llu-%llu", type,
357 			     *cfg_handle, *id);
358 		vdev->dev_no = *cfg_handle;
359 		vdev->port_id = *id;
360 	}
361 
362 	vdev->dev.parent = parent;
363 	vdev->dev.bus = &vio_bus_type;
364 	vdev->dev.release = vio_dev_release;
365 
366 	if (parent == NULL) {
367 		dp = cdev_node;
368 	} else if (to_vio_dev(parent) == root_vdev) {
369 		for_each_child_of_node(cdev_node, dp) {
370 			if (of_node_is_type(dp, type))
371 				break;
372 		}
373 	} else {
374 		dp = to_vio_dev(parent)->dp;
375 	}
376 	vdev->dp = dp;
377 
378 	/*
379 	 * node_name is NULL for the parent/channel-devices node and
380 	 * the parent doesn't require the MD node info.
381 	 */
382 	if (node_name != NULL) {
383 		(void) snprintf(vdev->node_name, VIO_MAX_NAME_LEN, "%s",
384 				node_name);
385 
386 		err = mdesc_get_node_info(hp, mp, node_name,
387 					  &vdev->md_node_info);
388 		if (err) {
389 			pr_err("VIO: Could not get MD node info %s, err=%d\n",
390 			       dev_name(&vdev->dev), err);
391 			kfree(vdev);
392 			return NULL;
393 		}
394 	}
395 
396 	pr_info("VIO: Adding device %s (tx_ino = %llx, rx_ino = %llx)\n",
397 		dev_name(&vdev->dev), vdev->tx_ino, vdev->rx_ino);
398 
399 	err = device_register(&vdev->dev);
400 	if (err) {
401 		printk(KERN_ERR "VIO: Could not register device %s, err=%d\n",
402 		       dev_name(&vdev->dev), err);
403 		put_device(&vdev->dev);
404 		return NULL;
405 	}
406 	if (vdev->dp)
407 		err = sysfs_create_file(&vdev->dev.kobj,
408 					&dev_attr_obppath.attr);
409 
410 	return vdev;
411 }
412 
413 static void vio_add(struct mdesc_handle *hp, u64 node,
414 		    const char *node_name)
415 {
416 	(void) vio_create_one(hp, node, node_name, &root_vdev->dev);
417 }
418 
419 struct vio_remove_node_data {
420 	struct mdesc_handle *hp;
421 	u64 node;
422 };
423 
424 static int vio_md_node_match(struct device *dev, void *arg)
425 {
426 	struct vio_dev *vdev = to_vio_dev(dev);
427 	struct vio_remove_node_data *node_data;
428 	u64 node;
429 
430 	node_data = (struct vio_remove_node_data *)arg;
431 
432 	node = vio_vdev_node(node_data->hp, vdev);
433 
434 	if (node == node_data->node)
435 		return 1;
436 	else
437 		return 0;
438 }
439 
440 static void vio_remove(struct mdesc_handle *hp, u64 node, const char *node_name)
441 {
442 	struct vio_remove_node_data node_data;
443 	struct device *dev;
444 
445 	node_data.hp = hp;
446 	node_data.node = node;
447 
448 	dev = device_find_child(&root_vdev->dev, (void *)&node_data,
449 				vio_md_node_match);
450 	if (dev) {
451 		printk(KERN_INFO "VIO: Removing device %s\n", dev_name(dev));
452 
453 		device_unregister(dev);
454 		put_device(dev);
455 	} else {
456 		pr_err("VIO: %s node not found in MDESC\n", node_name);
457 	}
458 }
459 
460 static struct mdesc_notifier_client vio_device_notifier = {
461 	.add		= vio_add,
462 	.remove		= vio_remove,
463 	.node_name	= "virtual-device-port",
464 };
465 
466 /* We are only interested in domain service ports under the
467  * "domain-services" node.  On control nodes there is another port
468  * under "openboot" that we should not mess with as aparently that is
469  * reserved exclusively for OBP use.
470  */
471 static void vio_add_ds(struct mdesc_handle *hp, u64 node,
472 		       const char *node_name)
473 {
474 	int found;
475 	u64 a;
476 
477 	found = 0;
478 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
479 		u64 target = mdesc_arc_target(hp, a);
480 		const char *name = mdesc_node_name(hp, target);
481 
482 		if (!strcmp(name, "domain-services")) {
483 			found = 1;
484 			break;
485 		}
486 	}
487 
488 	if (found)
489 		(void) vio_create_one(hp, node, node_name, &root_vdev->dev);
490 }
491 
492 static struct mdesc_notifier_client vio_ds_notifier = {
493 	.add		= vio_add_ds,
494 	.remove		= vio_remove,
495 	.node_name	= "domain-services-port",
496 };
497 
498 static const char *channel_devices_node = "channel-devices";
499 static const char *channel_devices_compat = "SUNW,sun4v-channel-devices";
500 static const char *cfg_handle_prop = "cfg-handle";
501 
502 static int __init vio_init(void)
503 {
504 	struct mdesc_handle *hp;
505 	const char *compat;
506 	const u64 *cfg_handle;
507 	int err, len;
508 	u64 root;
509 
510 	err = bus_register(&vio_bus_type);
511 	if (err) {
512 		printk(KERN_ERR "VIO: Could not register bus type err=%d\n",
513 		       err);
514 		return err;
515 	}
516 
517 	hp = mdesc_grab();
518 	if (!hp)
519 		return 0;
520 
521 	root = mdesc_node_by_name(hp, MDESC_NODE_NULL, channel_devices_node);
522 	if (root == MDESC_NODE_NULL) {
523 		printk(KERN_INFO "VIO: No channel-devices MDESC node.\n");
524 		mdesc_release(hp);
525 		return 0;
526 	}
527 
528 	cdev_node = of_find_node_by_name(NULL, "channel-devices");
529 	err = -ENODEV;
530 	if (!cdev_node) {
531 		printk(KERN_INFO "VIO: No channel-devices OBP node.\n");
532 		goto out_release;
533 	}
534 
535 	compat = mdesc_get_property(hp, root, "compatible", &len);
536 	if (!compat) {
537 		printk(KERN_ERR "VIO: Channel devices lacks compatible "
538 		       "property\n");
539 		goto out_release;
540 	}
541 	if (!of_find_in_proplist(compat, channel_devices_compat, len)) {
542 		printk(KERN_ERR "VIO: Channel devices node lacks (%s) "
543 		       "compat entry.\n", channel_devices_compat);
544 		goto out_release;
545 	}
546 
547 	cfg_handle = mdesc_get_property(hp, root, cfg_handle_prop, NULL);
548 	if (!cfg_handle) {
549 		printk(KERN_ERR "VIO: Channel devices lacks %s property\n",
550 		       cfg_handle_prop);
551 		goto out_release;
552 	}
553 
554 	cdev_cfg_handle = *cfg_handle;
555 
556 	root_vdev = vio_create_one(hp, root, NULL, NULL);
557 	err = -ENODEV;
558 	if (!root_vdev) {
559 		printk(KERN_ERR "VIO: Could not create root device.\n");
560 		goto out_release;
561 	}
562 
563 	mdesc_register_notifier(&vio_device_notifier);
564 	mdesc_register_notifier(&vio_ds_notifier);
565 
566 	mdesc_release(hp);
567 
568 	return err;
569 
570 out_release:
571 	mdesc_release(hp);
572 	return err;
573 }
574 
575 postcore_initcall(vio_init);
576